What was found
SMELLED BURNING RUBBER IN THE COCKPIT AT 14,000 FEET. SMELL DIMINISHED WITH POWER REDUCTION. APU WAS RUNNING. NO SMELL ON GROUND WITH APU RUNNING AND ENGINE OFF. INSPECTED ACU OILS & FANS, NO DEFECTS. RAN A/C AT POWER, NO BURNING SMELL NOTED AT THIS TIME. VISUALLY INSPECTED INLET & OUTLET ACM DUCTING. NO CONTAMINANTS NOTED IN DUCT WORK, INSPECTED OIL BOWLS, OIL IS CLEAR WITH NO LOSS INDICATED. REMOVED AND CLEANED FWD & AFT COALESCER SOCKS. REINSTALLED IN A/C.